package com.koorz.utils;

import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.net.URLEncoder;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;

import org.apache.commons.codec.binary.Base64;
import org.apache.commons.lang.StringUtils;

/**
 * 功能说明：加解密工具类 创建者：dongdong 创建时间：下午11:44:53 版本号：1.0
 */
public class CryptUtils {
	private final static String DES = "DES";
	private final static byte[] E_KEY = new byte[] { '1', '2', '3', '4', '5',
			'6', '7', '8' };
	private final static String UTF_8 = "UTF-8";

	/**
	 * 加密
	 * 
	 * @param src
	 *            数据源
	 * @param key
	 *            密钥，长度必须是8的倍数
	 * @return 返回加密后的数据
	 * @throws Exception
	 */
	public static byte[] encrypt(byte[] src, byte[] key) {
		// DES算法要求有一个可信任的随机数源
		try {
			SecureRandom sr = new SecureRandom();
			// 从原始密匙数据创建DESKeySpec对象
			DESKeySpec dks = new DESKeySpec(key);
			// 创建一个密匙工厂，然后用它把DESKeySpec转换成
			// 一个SecretKey对象
			SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);
			SecretKey securekey = keyFactory.generateSecret(dks);
			// Cipher对象实际完成加密操作
			Cipher cipher = Cipher.getInstance(DES);
			// 用密匙初始化Cipher对象
			cipher.init(Cipher.ENCRYPT_MODE, securekey, sr);
			// 现在，获取数据并加密
			// 正式执行加密操作
			return cipher.doFinal(src);
		} catch (Exception e) {
			throw new RuntimeException(e);
		}
	}

	/**
	 * 解密
	 * 
	 * @param src
	 *            数据源
	 * @param key
	 *            密钥，长度必须是8的倍数
	 * @return 返回解密后的原始数据
	 * @throws Exception
	 */
	public static byte[] decrypt(byte[] src, byte[] key) {
		try {
			// DES算法要求有一个可信任的随机数源
			SecureRandom sr = new SecureRandom();
			// 从原始密匙数据创建一个DESKeySpec对象
			DESKeySpec dks = new DESKeySpec(key);
			// 创建一个密匙工厂，然后用它把DESKeySpec对象转换成
			// 一个SecretKey对象
			SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);
			SecretKey securekey = keyFactory.generateSecret(dks);
			// Cipher对象实际完成解密操作
			Cipher cipher = Cipher.getInstance(DES);
			// 用密匙初始化Cipher对象
			cipher.init(Cipher.DECRYPT_MODE, securekey, sr);
			// 现在，获取数据并解密
			// 正式执行解密操作
			return cipher.doFinal(src);
		} catch (Exception e) {
			throw new RuntimeException(e);
		}
	}

	/**
	 * 数据解密
	 * 
	 * @param data
	 * @param key
	 *            密钥
	 * @return
	 * @throws Exception
	 */
	public final static String decrypt(String data, String key)
			throws Exception {
		return new String(decrypt(hex2byte(data.getBytes()), key.getBytes()));
	}

	/**
	 * 数据加密
	 * 
	 * @param data
	 * @param key
	 *            密钥
	 * @return
	 * @throws Exception
	 */
	public final static String encrypt(String data, String key) {
		if (data != null)
			try {
				return byte2hex(encrypt(data.getBytes(), key.getBytes()));
			} catch (Exception e) {
				throw new RuntimeException(e);
			}
		return null;
	}

	/**
	 * 加密
	 * 
	 * @param value
	 * @return
	 * @throws Exception
	 */
	public static String encrypt(String value) {
		byte[] data = encrypt(value.getBytes(), E_KEY);
		try {
			return URLEncoder.encode(new String(Base64.encodeBase64(data)),
					UTF_8);
		} catch (UnsupportedEncodingException e) {
			return null;
		}
	}

	/**
	 * 解密
	 * 
	 * @param value
	 * @return
	 * @throws Exception
	 */
	public static String decrypt(String value) {
		try {
			value = URLDecoder.decode(value, UTF_8);
			if (StringUtils.isBlank(value))
				return null;
			byte[] data = Base64.decodeBase64(value.getBytes());
			return new String(decrypt(data, E_KEY));
		} catch (UnsupportedEncodingException excp) {
			return null;
		}
	}

	/**
	 * 二行制转字符串
	 * 
	 * @param b
	 * @return
	 */
	private static String byte2hex(byte[] b) {
		StringBuilder hs = new StringBuilder();
		String stmp;
		for (int n = 0; b != null && n < b.length; n++) {
			stmp = Integer.toHexString(b[n] & 0XFF);
			if (stmp.length() == 1)
				hs.append('0');
			hs.append(stmp);
		}
		return hs.toString().toUpperCase();
	}

	private static byte[] hex2byte(byte[] b) {
		if ((b.length % 2) != 0)
			throw new IllegalArgumentException();
		byte[] b2 = new byte[b.length / 2];
		for (int n = 0; n < b.length; n += 2) {
			String item = new String(b, n, 2);
			b2[n / 2] = (byte) Integer.parseInt(item, 16);
		}
		return b2;
	}

	public static String getMD5(String src) {
		try {
			StringBuffer sb = new StringBuffer();
			MessageDigest md = MessageDigest.getInstance("MD5");
			md.update(src.getBytes(UTF_8));
			for (byte b : md.digest())
				sb.append(Integer.toString(b >>> 4 & 0xF, 16)).append(
						Integer.toString(b & 0xF, 16));
			return sb.toString();
		} catch (NoSuchAlgorithmException e) {
			return null;
		}catch (UnsupportedEncodingException e) {
			return null;
		}
	}
	
	public static void main(String[] args) {
		System.out.println(getMD5("321456ydd"));
	}
}
